Okay, What about header gaskets.

I am a silicone hater, but on a Mopar, Permatex Copper seals incredibly well. Not a lot, just a skim coat on the gasket. I have had bolts come loose and the gasket didn't leak. Same with a buddy of mine on his 69 Coronet R/T 440 Magnum. He had a header bolt fall out and they didn't leak.